Feed water regulator



Sept. 29, 1931.

V. V. VEENSCHOTEN FEED WATER REGULATOR 2 Sheets-Sheet 1 -Filed Sept. 17, 1927 Sept; 29, 1931.

v. v. VEENSCHOTEN l,82 4,97l

FEED WATER REGULATOR Y Filed Sept. 17, 1927 2 Sheets-Sheet 2 J4 F29: J .07

Patented Sept. 29, 1931- UNITED STATES PATENT OFFICE EQUIPMENT COMPANY, OF VANIA ERIE, PENNSYLVANIA, A CORPORATION OF PENNSYL- FEED WATER REGULATOR Application filed September 17, 1927. Serial No. 220,113.

This invention relates to feed water regulators for boilers. One object of the invention is to provide a suitable method for feeding water to boilers, particularly in cases of boilers operating under high'pressures and capacities and where load changes are frequent and material. The invention however is applicable to boilers operated otherwise. Another object of the invention is to provide suitable means for carrying out the method. Other objects of the invention will be apparent from a consideration of the accompanying drawings and the following description thereof.

Of the drawings Fig. 1 is an elevation more or less diagrammatic, of a boiler and feeding apparatus therefor which embody the features of my invention; Fig. 2 is an enlarged detail view of a portion of the operating means of the feed water regulators of the system; Fig. 3 is a plan view of the elements of Fig. 2; Fig. 4 is a detail'sectional view of one of the elements; Fig. 5 is an elevation of a modified boiler feed water regulator system; Fig. 6 is an enlarged sectional view of the feed water valve which may be used with either system; and Fig- 7 is a further enlarged View of the valve plunger.

The method of feeding water to boilers which I have invented has for its object feeding water to the boiler substantially if not exactly in proportion to the load on the boiler, that is, to the amount of steam that is flowing from the boiler; the object' being to vary'the inflow of water to the boiler through the feed water valve as the outflow of steam varies, so that the input. to the boiler will continuously be substantially the same as the output. However, with boilers acting at high capacities and high steam pressure, particularly with materially varying loads, very material variations in the water level are produced by the generation of steam in the body of the water and the belching up of the steam through the water, the amount of this generation and the volume of the steam depending upon the intensity of the fire, the steam pressure, and 50 the like. Hence, it frequently happens that 'less tendency of t the water level elevation will materially vary even though the input of the water is substantially the same as the outflow of the steam.

A further object of my invention therefore is to prevent undue variations in the water level elevation owing to the variations in steam generation and steam pressure with varying loads. And with this object in view I provide means for maintaining substantially constant or within certain limits the water level elevation in the boiler; in general, the object being to retard or neutralize the tendency of the water level to vary, or to tend to bring the level back to the-normal or constant level elevation when variations do occur.

It is to be understood however that, in ordinary boiler opleration, there is more or e water level to fluctuate above and below a certain normal elevation irrespective of the outflow or input, and more or less irrespective of the variations in the mass of entrained steam. These fluctuations are all of-a minor nature and are not considered of material consequence, the

normal water level elevation being considered the average elevation at the normal or average load irrespective of the variations therefrom of such fluctuations.

In providing apparatus for carrying out my method I prefer to use a thermostat regulator. The type of thermostat regulator which I prefer to use is well known in the art under the trade name of the Copes regulator and comprises an inclined expansible thermostat which is mounted upon a suit able support. The upper end of the thermostat is'connected to the steam space of the boiler and the lower end of the thermostat communicates with the water space of the boiler. As is understood, in such a case the Water will stand in the thermostat substantially at the same elevation as in the boiler and as the water level in the thermostat rises or sinks the thermostat will contract or expand in length as the case may be and this contraction or expansion is caused, by suitable means, to operate accordingly the feed water valve of the boiler.

In this case, as a part of the system, I employ a vertical thermostatic tube 10, supported on bars 11. To avoid confusion the bar 11 on the front of the tube 10 is not shown except in Fig. 3.

The upper end of the thermostat 10 in this case is not directly connected to the boiler, but it is connected by pipes 13 to the pipe 26 of the steam main 14 of the boiler system, and in this main an orifice 25 is inserted, the opening of the orifice being materially less than the bore of the pipe 14. As a consequence when the steam flows from the boiler there will be a drop in pressure between the boiler and the pipe 26 to which the pipes 13 are connected. In other words, the pressure of the steam in the pipe 26 will decrease as the flow through the steam mains increases. This decrease in pressure in the pipe 26 will extend to the pipes 13 and the thermostat 10 and, as a consequence, the water will be forced higher in the thermostat 10 by the pressure of the steam and water in the boiler acting through the pipe 16 which connects the boiler with the lower end of the thermostat. When this occurs the tendency will be to elevate more the valve arm 19 and to open further the feed water valve 24 and thus compensate for the increased outflow of steam.

The means which I provide for operating the valve by the contraction and expansion of the thermostat 10 comprise the regulator lever 17, a connecting rod 18, and a ,valve lever 19. The upper end 20 of the thermostat is fixed to the support 11 and the lower end 21 is free to move sufficiently up and down as the thermostat contracts or expands. The fulcrum 15 of the lever 17 is supported inany suitable manner. In this instance the vmanner of supporting the fulcrum is explained hereinafter. The end of the tube 10 is pivotally connected to the lever 17 by the pivot 65.

Obviously, as the water in the tube rises,

' owing to an elevation in the water level in the boiler, the thermostat will contract and the rod 18 will be raised, elevating the arm 19 against the weight of the mass 22. This, in the ordinary manner, will elevate the plunger 23 of the feed water valve and open the ports of the valve more so as to increase the inflow of water to the boiler.

However, I have found that the opening of the valve ports 30 as the plunger 23 rises must increase at a lesser rate than the movement of the plunger in order to supply suflicient water through the feed water valve to compensate for the increased outflow of steam. Assuming the increase in outflow to be 10% the opening of the valve must increase 10% in order to supply as much water as is passin off in the form of steam. But there will %e a tendency for the valve to open to a greater extent, as the drop in pressure atthe point 21 and the consequent elevation of water in the thermostat 10, varies as the square of the steam flow variations. Hence, in order to full compensate for the loss in steam by the inflowing water it is necessary for the valve shaped somewhat as indicated, the shape of the effective edges of the port being substantially that of parabolas, though this will depend somewhat upon the special conditions which exist and under which the boiler is operated. When the shape of the ports of the valve is suitable the inflow of water through the ports will be substantially equal to the outflow of water in the form of steam. It is to be understood that the valve opens as the plunger is raised, so that the ports increase in size at a lesser rate than the movement of the valve plun er.

However, as hereinabove indicated, owing to the variations in the amount of steam generated in the body of the water of the boiler, and for other reasons, even though the mass of water in the boiler may remain substantially constant there are often material variations in the water level, or at least the elevation of the water level varies in more or less an undesirable manner. To eliminate this tendency, and particularly to limit the variation in level within certain limits, I install, in connection with the thermostatic tube 10, a second tube 35 which is mounted in an ordinary manner on bars 36. The front bar 36 is shown only in Fi 3. The end 37 of the tube is held in a fixed position by the bars. This second tube is operatively connected, by means of pipes 38 and 39 respectively to the steam space and the water space of the boiler, and hence, the tube contracts and expands more or less as the water level in the boiler rises or sinks.

In the'present embodiment of my invention the tube 35 is arranged to control the position of the fulcrum 15 of the lever 17.

The end 40 of the tube 35 is connected to a bell crank lever 41 by means The fulcrum 43 of this lever support 36 and the arm 44 of the lever supports the fulcrum 15. Thus as the tube 35 contracts or expands theiiulcrum 15 will be raised or lowered accordingly and this in turn will lower or raise the lever 17 and the arm 19 accordingly.

A consideration of the mechanism will show that, as the water level in the, boiler, and hence in the tube 35, rises, the tube 35 will contract, elevating the fulcrum 15 of the lever 17 and thus lowering the arm 19 and closing somewhat more the ports of the plunger 23. As a consequence, theamount of inflow to the boiler will be decreased and there will be a tendency to bring the water level elevation back to normal, or at least to retard the risein elevation.

Obviously the two regulators will coact of a pivot 42. is fixed to the ports to be 'in water level elevation occurs simultaneously or otherwise the tube 35 will vary the opening of the feed water valve so as to compensate for the variation in water level and tend to bring it back to normal. In neither case will the action of the thermostat interfere .with the normal action of the other thermostat, but they will both coact to carry out my method of feeding the water as nearly equal to the amount of steam used as is consistent with keeping the water level sufiiciently near the normal level.

In Fig. 5 I illustrate a modified form of feed water control, which will carry out my method and is similar in many respects to that of Fig. 1. The thermostat tube 50 may be in all respects similar to the thermostat tube and its connection with the feed water valve 24 may be in all respects similar. The tube 51 is similar to the tube 10, and similarly supported. And it is associated with the tube in substantially the same way as the tube 10 is associated with the tube 35. But the tube 51 has its lower end connected with the steam main 52 by means of pipes 54 on one side of an orifice 53 therein, andthe other end of the tube is connected to the steam main 55 by means of pipes 56.

As a consequence the pressure effects of the steam on the lower end of the tube will be greater than that on the upper end, owing to the falling pressure through the orifice53.

In order to maintain a water column in the tube 51 the pipe 54 is positioned below the pipe 52 so that the condensed water from the steam will fill this pipe and ultimately will be forced upwardly into the tube 51. Thus an elevation of the water in the tube 51 will be maintained depending upon the relative steam pressures and the weight of the water in the tube 51. v

If properly adjusted, the water level elevation in the tube 51 will be maintained in the central portion of the tube and will vary as the outflow of steam through the mains varies. Any increase in flow of the steam will cause the water level to rise and the contraction of the tube, by means of the connecting rod 57, will elevate the leversv 17 and 19 and open further the valve 24, thus compensating for the increased flow in steam. v In order to insure a su cient supply of water for the tube 51 I provide a tank which communicates with the steam main 52. Ultimately this tank will become full of condensed water and thus a sufiicient supply will be provided for the variations in water level in the tube 51. In order to adjust the Water level elevation in the tube 51 the fall in pressure through the orifice may be varied in any suitable manner. I prefer for the purpose to use the orifice of a gate valve 53, the port of which may be varied as.

desired.

In the operation of my system of feed Water control it is desirable to be able to adjust the amount of operation of the valve produced by a given amount of contraction or expansion of either of the tubes.

the purpose of this adjustment with refer-- ence to the tube 10 I provide means for adjusting the distance between the pivot and the fulcrum 15 of the lever 17. These means comprise a block 66 which issupported by the pivot 65. This block is adjust-ably fixed to the lever 17 so that it may be shifted longitudinally with reference to that lever. The lever 17 has a fork 67 and in the block 66 is a slot 68 in which plays a bolt 69 passing through the tines, of the fork. By looseningthe bolt the block may be shifted longitudinally of the lever and thus the distance between the pivots 65 and 15 may be varied.

Similarly the distance between the pivots 42 and 43 of the lever 41 may be varied by means of a block 7 O movably mounted in the arm 71 of the bell crank lever 41.

I claim as my invention:

1. In a boiler system a boiler having a steam main and a feed water valve, said main having a restricted orifice therein, a feed-water regulator comprising a thermostatic tube, one end of said tube being operatively connected with the water space of the boiler, the other end of the tube being operatively connected with said steam main with the orifice between the point of connection and the boiler, and means operatively For connecting said thermostatic-tube with said valve.

2. In a boiler system a boiler having a steam main, said main having a restricted orifice therein, a feed water regulator comprising a thermostatic tube, one end of said tube being operatively connected with the water space of the boiler, the other end of the tube' being operatively connected with said steam main with the orifice between the point of connection and the boiler, a

feed-water valve operatively connected with said boiler, and means operatively connect- 'ing said thermostatic tube with said valve in combination with a second thermostatic tube operatively connected with the water space and the steam space of the boiler, said second tubebeing operatively connected with the said means which connects the first mentioned tube with said valve.

3. In a boiler system a boiler having a steam main, said main having a restricted -orifice therein, a feed water regulator com-.

feed-water regulators, said boiler comprising a feed-water valve, a water space, an adjacent steam space and said boiler being connected to a more remote steam space, said; regulators both operatively communicatin with the said water space one with the said adjacent steam space and one with the 'said remote steam space, and means operatively connecting said regulator system with said valve, the capacity of the ports of said valve being shaped so as to vary in capacity substantially as the square root of the movement of the valve.

5. The combination of a boiler and a feedwater regulator system therefor, said boiler comprising a feed-water va'lve, a water space, an adjacent steam space, and said boiler being connected to a more remote .steain space, and means operatively connecting said regulator system with said valve,'s aid regu-' lator system comprising two feed-water regulators, both being operatively connected to said water space, one being operatively connected tothe adjacent steam;space, and the otherbeing operatively connected to the remote steam space, said means comprising two operatively connected levers, one of said levers being operatively connected with said valve and with one regulator, and the other said main, the ports of said valve being shaped so that the rate of movement of the valve as it opens, will exceed the rate of increase in the opening of the ports.

8. A valve comprising a cylindrical plunger having ports in its wall, the opposing edges of said ports being convex with the effective edges adjacent one end of the ports being spaced apart farther than elsewhere, and adjacent the other end of the ports the efi'ective edges being spaced apart less than elsewhere.

9. A valve, comprising a cylindrical plunger having ports in its wall, the opposing edges of said ports being tapering with the efiective edges adjacent one end of the ports' being spaced apart farther than elsewhere, and adjacent the other end of the ports the effective edges being spaced apart less than elsewhere, the wider end of the ports being first to open.

In testimony whereof, I hereunto set my hand.

VINCENT V. VEENSCHOTEN.

lever being omaratively connected with the other regulator, the ports ofsaid -valve being shaped so that, as the valve opens, its rate of movement will be greater than the rate of increase in the opening of the ports.

6. In a steam boiler system, a steam main,

and a feed-water valve, means actuated by variations in the drop in pressure of the steam in said main, said means being operatively connected with said valve, the ports of said valve being shaped so as to vary in capacity substantially as the square root of the valve movement.

7. In a steam-boiler system, a steam main and a feed water valve, means operatively connecting said main and said valve, and

adapted to moye said valve at a greater ra e. than the rate of increase in steam flow m w 

